The use of pre-manufactured, standard integrated circuit chips is common in the manufacture and the development of various hardware systems. These integrated chips act as building blocks in the design and manufacture of complicated circuit designs and other hardware systems. For example, the manufacture of a personal computer utilizes dozens of pre-manufactured integrated chips.
Even though these integrated chips are manufactured according to pre-defined specifications, the accuracy and functionality of these chips is greatly affected by external and collateral factors. These external factors include variations in the manufacturing processes, changes in the environment temperature, and changes in the power supply.
The actual performance parameters of a chip may vary from nominal specifications due to uncontrollable variations in the manufacturing processes. For example, a temperature variation in the manufacturing plant during the manufacturing process can change the process profile and therefore change the outcome manufacturing values of an integrated chip. Similarly, a change in the density of diffusion also can change the process profile and therefore change the performance parameters. These performance parameters include the speed of the integrated circuit chips.
After the integrated circuit chip has been manufactured, changes in the ambient or environment temperatures also affect the functionality and utility of an integrated chip. Each standard integrated circuit chip is manufactured to operate nominally at a standard room temperature and should accommodate some temperature variation. However, in actual practice, room temperatures vary drastically from one geographic location to another due to thermodynamic elements. Accordingly, the functionality and the accuracy of an integrated circuit chip also varies depending on the ambient temperature.
The functionality of an integrated chip also is affected by variations in the power supply. Variations in the power supply voltages typically result from fluctuations in the commercial supply of power. The power supply sources also utilize various voltage regulators. The power supply variations also may result from the differences in the manufacturing processes of the different voltage regulator vendors.
Thus, even though an integrated chip may have been manufactured according to pre-defined specifications, the variations in the manufacturing process, the ambient temperatures, and the power supply may cause an integrated chip to fluctuate from its intended operation parameters. For example, two transistors manufactured according to an identical specification may have very different speed characteristics. In different lots, there will be fast, slow and nominal transistors, with some noticeable variation.
These process, temperature and power supply variations are undesirable especially for applications where extreme precision is demanded and for which even the slightest deviation from original specification can result in unacceptable circuit performances. Thus, there exists a need for a system to compensate for these commonly known process, temperature and power supply variations, and therefore increase the utility and accuracy of integrated circuit chip.